Corbyn, 70, and Trump, 73, have far more in common than Boris and Trump. Jeremy and Donald are both anti-establishment insurgents who have been married three times. They both like dictators and dislike Nato. They both have embarrassing pasts which should disqualify them from high office. When they were elected to lead their parties, Trump and Corbyn were both dismissed as jokes but they turned their joke-status to their advantage.

The success of both men was seen as a sign that their respective parties had gone mad — but it turned out the electorate was just as mad, and the laughing stopped. Both men then got lucky: they stood against seemingly invincible women who took victory for granted and turned voters against them with their arrogance.

Until recently, the British prided ourselves on how sensible our politics was compared to the populism ravaging so much of the developed world. Look, we said, Ukip is perishing; the BNP is all but dead. We’d never fall for a rabble-rouser like Trump. But this analysis missed a rather important point: Corbyn is the torchbearer of British populism, and his politics is surprisingly popular.